Apparatus include an inkjet pen with a body that defines a first ink reservoir configured to contain a first ink, and a second ink reservoir configured to contain a second ink. A print head is also included, and is operatively supported by the body, wherein the first ink reservoir and the second ink...http://www.google.com.au/patents/US7033012?utm_source=gb-gplus-sharePatent US7033012 - Ink containment apparatus and methods for inkjet printers
